Improvement in cupola-furnaces



Patented J'une19,'1877.

NVENTOH J Mm I I L u a n a I u o 0 00 U. B. STRIBLING.

CUPOLA FURNACE.

N. PETERS, FHOTO-UTHDGRAFHER, WASHINGTON. D C.

fTTEST URIAH B. STRIBLING, OF MADISON, INDIANA, ASSIGNOB TO HIMSELF ANDISAAC N. TODD, OF SAME PLACE.

IMPROVEMENT IN CUPOLA-FURNACES.

Specification forming part of Letters Patent N 0. 192,106, dated June19, 1877; application filed April 11, 1877.

To all whom it may concern;

Be it known that I, Uernn B. STRIBLING, of Madison, in the county ofJefferson and State of Indiana, have invented certain Improvements inOupola-Furnaces, of which the following is a specification;

This invention relates most particularly, but not wholly, to that classof cupola-furnaces used for melting cast-iron; and the inventionconsists, partly, in constructing the cupola with a double shell, thusforming an annular air-chamber, which receives the blast from theblower, warms or heats it, and then delivers it to the melting chargethrough a series of tuyeres; also, partly in the peculiar con-.

struction of the tuyeres and partly in their general arrangement, all ofwhich will be hereinafter set forth.

In the drawings, Figure 1 represents a rear elevation ofa cupolaembodying my invention, a portion of the shells being broken away toshow the interior. Fig. 2 is a cross-section of Fig. 1, taken in theplane of the line a; as. Fig. 3 is an enlarged sectional view,showing-the construction of the tnyeres.

In the ordinary construction of the ironmolders cupola the wall or shellof the same is single, and cold air direct from the blower is admittedthrough tuyeres from opposite sides.

In my improved form, let A represent an outer tubular shell, which maybe of plate or sheet iron, and B an inner shell,'similarly constructedand arranged concentric with the first. This leaves an annular air spaceor chamber, a, between the shells, which should be capped by aring-cover, b, so as to make the chamber a. air-tight. These shells maybe mounted on a platform or stand, 0, in the usual way, and the innershell lined with firebrick c.

D is the charging-door, the frame of which connects the twoshells, so asto prevent the escape of air from the chamber a. The opening E fortapping out is constructed in a similar manner.

F is the blower-pipe, which taps the outer shell above thecharging-door, near the'top of said shell.

G G are the tnyeres. These I have shown arranged in three tiers, thoseof the lower tier being the largest and those of the upper tier thesmallest; The upper tier contains twelve tuyeres, and the two lower sixeach. No one is directly above any other. By this arrangement the blastis more evenly distributed as it enters the melting-chamber than in theordinary arrangement,

The tuyeres are peculiarly constructed, as clearly shown in Fig. ,3, Atube of cast-iron or some suitable refractory material, long enough toextend through both sheds and the fire-brick lining, is' cut away at d,where the tuyere crosses the annular space a, to admit air from theblower into the hollow of the tube. At 6, in the closed outer end of thetuyere, is a small hole, usually kept plugged up when the furnace is inoperation. This hole, when opened, allows the operator to view theinterior of the furnace, and also permits the insertion of a clearingbar or rod to remove obstructions from the mouth of the tuyere, shouldit become stopped. The open ing d should equal in area the caliber ofthe tuyere, and the hole 0 may equal the tuyere in caliber; but in thoseof large caliber I prefer to make it less.

In the precise arrangement herein shown the upper tier of tuyeres have acaliber of 1.5 inches, the second 2.0 inches, and the lower tier 3.0inches; but these proportions may be varied to some extent withoutdeparting from the principle of my invention.

The area of the blower-pipe F should equal or exceed the combined areasof the tuyeres used, and I prefer to connect it with the outer shell atthe top or upper part of the same, anywhere above the charging-door D,so that the air may become heated in its passage down to the tuyeres,which are usually placed but a short distance above the melting-hearthof the cupola. Two or more blower-pipes may be used, and they may tapthe outer shell at varying heights, as convenience and circumstances maydictate; but I believe the arrangement shown capable of producing thebest results. I i

It is obvious that the higher up the outer shell is carried the higherwill be the temperature of the blast, and in practice I have built themthirty feet high; but this will also vary according to the circumstancesof the case.

The advantage resulting from the use of a warm or hot blast is that themolten metal flows more freely into the mold, and makes more perfectcastings. By its use, also, a greater'proportion of scrap-iron can beused than with a cold-blast in the production of the same quality ofcastings.

Having thus described my invention, what I claim as new, and desire tosecure by Letters Patent, is as follows:

1. A cupola-furnace having a double shell extending from the platform orfire-bed G to a point above the charging-door D, a blowerpipe, F,connected with the air-space a, as shown, and two or more rows oftuyeres, G G, cut away at d to form side inlets, and supported at theirouter ends in the outer shell A, all in the manner substantially as setforth.

2. In combination with the shells A B, arranged to form a continuousannular airspace, a, extending from the fire-bed at O to the ring-coverb above the charging-door D, the tuyeres G G, cut away at d to form aside inlet, the back ends being supported in the outer shell A,substantially as herein shown and described.

3. In a cupola-furnace, a tuyere provided with an opening in the side toadmit the airblast, and an opening in the outer end to adunit of viewingthe interior or clearing out the tuyere, substantially as set forth.

4. In a cupola-furnaoe having a double shell and an air-space, a,extending from a point below the tuyeres to a point above thecharging-door, a series of tuyeres of difierent caliber, in tiers, thesmallest above and the largest below, the said tuyeres being supportedat .the outer end in the outer shell, all substantially as herein setforth.

5. The combination of the outer shell A, extending from a point belowthe tuyeres to a point above the charging-door, inner lined shell B,blower pipe or pipes F, and tuyeres G G, the latter being of differentcalibers, having side inlets d and openings in the outer ends forviewing, and arranged in tiers, substantially as shown.

In witness whereof I have hereunto signed my name in the presence of twosubscribing witnesses.

UBIAH B. STRIBLING.

Witnesses:

Jos. TODD, WALTER W. BENTLY.

